The ring modulator described in part I of this paper is designed here for two operating wavelengths 1550nm and 1310nm. For each wavelength, three structures are designed corresponding to three values of polymer slot widths (40, 50 and 60nm). The performance of these modulators are simulated using COMSOL software (version 4.3b) and the results are discussed and compared with theoretical predictions. The performance of intensity modulation/direct detection short range and long rang optical communication systems incorporating the designed modulators is simulated for 40 and 100Gb/s data rates using Optisystem software (version 12). The results reveal that an average energy per bit as low as 0.05fJ can be obtained when the 1550nm modulator is designed with a phase shifter length equals twice the coupling length.
Optimized Link State Routing Protocol (OLSR) is an efficient routing protocol used for various Ad hoc networks. OLSR employs the Multipoint Relay (MPR) technique to reduce network overhead traffic. A mobility model's main goal is to realistically simulate the movement behaviors of actual users. However, the high mobility and mobility model is the major design issues for an efficient and effective routing protocol for real Mobile Ad hoc Networks (MANETs). Therefore, this paper aims to analyze the performance of the OLSR protocol concerning various random and group mobility models. Two simulation scenarios were conducted over four mobility models, specifically the Random Waypoint model (RWP), Random Direction model (RD), Nomadic Co
... Show MoreSpatial data observed on a group of areal units is common in scientific applications. The usual hierarchical approach for modeling this kind of dataset is to introduce a spatial random effect with an autoregressive prior. However, the usual Markov chain Monte Carlo scheme for this hierarchical framework requires the spatial effects to be sampled from their full conditional posteriors one-by-one resulting in poor mixing. More importantly, it makes the model computationally inefficient for datasets with large number of units. In this article, we propose a Bayesian approach that uses the spectral structure of the adjacency to construct a low-rank expansion for modeling spatial dependence. We propose a pair of computationally efficient estimati
... Show MoreThis review highlights recent advances in the development and use of eco-friendly polymeric membranes made from polymer blends for treating oily wastewater, a major source of environmental pollution. Among treatment options, membrane separation stands out because of its high efficiency and ability to selectively remove oil from water using semi-permeable barriers. The focus of this review is on polymeric membranes derived from polymer blends, which show improved mechanical strength, thermal stability, and resistance to fouling. Additionally, the role of nanomaterials such as titanium dioxide, graphene oxide, and iron nanoparticles is discussed for their ability to boost membrane porosity, permeability, and oil separation efficiency.
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Due to the continuing demand for larger bandwidth, the optical transport becoming general in the access network. Using optical fiber technologies, the communications infrastructure becomes powerful, providing very high speeds to transfer a high capacity of data. Existing telecommunications infrastructures is currently widely used Passive Optical Network that apply Wavelength Division Multiplexing (WDM) and is awaited to play an important role in the future Internet supporting a large diversity of services and next generation networks. This paper presents a design of WDM-PON network, the simulation and analysis of transmission parameters in the Optisystem 7.0 environment for bidirectional traffic. The sim
... Show MoreCongestion management features operate to control congestion once it occurs. One way that network elements handle an overflow of arriving traffic is to use a queuing algorithm to sort the traffic, and then determine some methods of prioritizing it onto an output link. Each queuing algorithm was designed to solve a specific network traffic problem and has a particular effect on the network performance. The work presented in this thesis deals with important issue that is the quality of service (QoS) techniques, which can be integrated to enhance the operation of the network. The quality of service is the collective effect on service performance, which determines the degree of satisfaction of a user of the service. In this thesis, packet sched
... Show MoreBackground: Mobile phones are approximately widely used everywhere like in hospital wards, clinics and universities as well as biomedical laboratories. They have become very important tool in students’ life. In contrast, these tools carry many harmful bacteria which are responsible for infectious diseases in human because they serve as a reservoir for different pathogens. Current study was aimed to isolate bacteria from students’ mobile phones at the Institute of Medical Technology/Al-Mansour/The Middle Technical University, Baghdad, Iraq. Also, the study investigated microbial resistance to many antimicrobial agents as well as the appropriate remedial measures. Method: Four hundred and fifty swabs from mobile phones were collected from
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